Reg

How can I determine how effective a balun is?? I am working at 137 MHz
and cant consider a radiation pattern range of any kind.
I have been trying a coil of small coax in a relatively low loss ferrite
toroid and then slipping a high permeability tube of more lossy ferrite on
the coax to the receiver. I thought the higher reactance with a reasonable
Q might minimize the current conducted along the feed line. Then, any
currents that do get by the reactive coil might get disipated in the lossy
and high permeability ferrite tube section.

Since I'm working without much knowledge and almost no test equipment, I'd
sure appreciate any information about how to evaluate baluns at VHF.

Jerry

"Reg Edwards" wrote in message
...

NOW AVAILABLE ** New Program "BALCHOKE.exe"

This program is very similar to program CHOKEBAL The main change is to
input data. The ferrite core is rectangular in shape and defined in terms
of
thickness and length instead of a circular core diameter. The size of the
core is described more conveniently in terms of the outside diameter of
the
ferrite ring instead of the diameter of the mean magnetic path.

The opportunity has been taken to provide, in the author's opinion, a
better
statistical way of estimating percent current unbalance in the twin-wire
transmission line. There are also better program operating notes.

Although most numerical results are identical this second version of the
program is recommended.

Program size about 36 kilobytes. Download program BALCHOKE from website
below in a few seconds and run immediately from a desktop icon.
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Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
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